See's Candies! I've seen some stores in Hong Kong and Japan carry them, but never in Korea. My host family in Korea and Singapore loved the peppermint ones.
Being from Texas, you might get some Tex-Mex goodies as well. I'm a Texas girl myself, and I brought these https://www.amazon.com/Vero-Covered-Flavored-Lollipops-Pieces/dp/B0000ICLLS chili-mango lollipops. Kind of weird, but they were definitely a hit!
Not spicy at all, but still delicious. I'd be curious about some of the answers to your questions also, I need me some real spicy candy!
have you looked at mexican candy? theres lots of mango flavored options https://www.amazon.com/Vero-Covered-Flavored-Lollipops-Pieces/dp/B0000ICLLS
My fierce addiction to Vero Mango suckers feels both seen and attacked.
btw if anyone wants to try them:
They're $4.50 for a bag of 40 in stores.